Gastric ulcer is a common disease of the digestive system, and easy to be recurred. With the stress of modern life, people are suffered from mental stress and work pressure, which led to the increasing incidence of gastric ulcers, and this disease endangers people's health. At present, some anti-ulcer drugs, such as ranitidine, omeprazole, and etc, are often clinically applied to the patient. Although the short-term efficacy of the chemical drugs is obvious, there are some side effects after taking those drugs. Therefore, people begin to research and develop new type of anti-ulcer drugs with high-efficiency and low toxicity. Based on long-term history of clinical practices, traditional Chinese medicine has been proved to have natural advantage and there is wide clinical application value for us to find and dig natural active ingredients or fractions from traditional Chinese herbal medicines for the treatment of gastric ulcer.
Albizzia chinensis (Osbeck) Merr. belongs to genus Albizzia, family Legume, and its medicinal part is mainly from the bark of the tree. Normally the bark contains tannin with the property of relieving diarrhea with astringents and promoting granulation and wound healing. It can be used for the treatment of enteritis, diarrhea, and dysentery. (The compilation of Chinese herbal medicine, compiled by the compilation of Chinese Herbal Medicine editorial group, Second Edition, 1986, volume 2, p 768). It was also reported that triterpene saponins (Albizzia julibrissin oxytocin) from the bark of Albizzia chinensis played a role in uterine contraction (The dictionary of traditional Chinese Medicine, compiled by Jiangsu New Medical College, 1998, volume 1, p 937). Recently, a series of complex triterpenoid saponins with cytotoxic activity isolated from of the bark of Albizzia chinensis have been published by the inventors (J. Nat. Prod. 2009, 72, 632-639; Carbohydr. Res. 2010, 345, 1877-1881). Moreover, we have also found that Albizzia chinensis extracts have sedative and hypnotic activity (China Patent Publication No. CN 101766676A). So far, there was no report about anti-gastric ulcer or anti-chronic gastritis pharmacology activity and proton pump inhibitory activity of the extract of the bark of Albizzia chinensis. 